Problem: $ (-16.8 \div 0.7) \div -0.3 $
Solution: $ = -16.8 \div (0.7 \times -0.3)$ $ = -16.8 \div -0.21$ ${0}$ ${2}$ ${1}$ ${1}$ ${6}$ ${8}$ ${0}$ $\text{Shift the decimal 2 to the right.}$ ${1}$ $\text{How many times does }21\text{ go into }{1}\text{?}$ ${0}$ ${1}$ $-\vphantom{0}$ ${1}\div21={0}\text{ or }21\times{0} = {0}$ ${6}$ $\text{How many times does }21\text{ go into }{16}\text{?}$ ${0}$ ${1}$ ${6}$ $-\vphantom{0}$ ${16}\div21={0}\text{ or }21\times{0} = {0}$ ${8}$ $\text{How many times does }21\text{ go into }{168}\text{?}$ ${8}$ ${1}$ ${6}$ ${8}$ ${0}$ $-\vphantom{0}$ ${168}\div21={8}\text{ or }21\times{8} = {168}$ ${0}$ $\text{How many times does }21\text{ go into }{0}\text{?}$ ${0}$ ${0}$ ${0}$ $-\vphantom{0}$ ${0}\div21={0}\text{ or }21\times{0} = {0}$ Since both $-16.8$ and $-0.21$ are negative, the result is positive. $-16.8 \div -0.21 = 80$